When the Government announced the new children's savings vehicle, Mark Hoban, financial secretary to the Treasury, said: "Junior Isas allow parents and family friends to contribute to children's savings and will strengthen the savings culture. I look forward to seeing these on the high street in a few months' time."

The take-up of the Jisa has been woeful when compared to the popularity of the previous child's savings vehicle the Child Trust Fund (CTF).

Six million children born between 2002 and 2011 applied for a CTF, an investment vehicle that was restricted to just 14 products. Yet despite the simplified nature of the Jisa, 100 times fewer children have applied.

Any child under the age of 18 who is resident in Britain and does not already have a CTF is eligible to open a Jisa. If you are aged 16 or over you can open a Jisa yourself, otherwise a parent or guardian will have to do so on your behalf.

Just like an adult Isa, you can chose to shield cash, stocks or investment funds from the taxman, but unlike the adult Isa, investments cannot be cashed in before the Jisa – and the child – mature at 18.

Parents can invest up to £3,600 every tax year, which runs from April 6 to April 5. If you do not use your tax-free allowance each year, you lose it – you do not get to roll it over. If a baby born this year took advantage of their Jisa allowance every year until 2029, assuming annual growth of 4pc a year, the Jisa would be worth £122,400 on maturity.

Investment options include lump sum investing and regular saving from £50 a month. You can also save £3,600 a year in a cash Jisa.

Danny Cox of Hargreaves Lansdown said, “Junior ISAs have had a slow start but this is not surprising given the current economic climate. New products always take time to bed in and not all providers were ready at launch."

"It’s not helped by the fact that children with Child Trust Funds are not eligible for Junior ISA, disadvantaging around 6 million children," added Mr Cox.

"At the very least transfers should be allowed between the two. Running two separate schemes adds complexity and doesn’t encourage a savings culture."